Try:
systemctl --user status pipewire
if you see:
pipewire.service - PipeWire Multimedia Service
Loaded: loaded (/usr/lib/systemd/user/pipewire.service; disabled; vendor preset: enabled)
Active: inactive (dead)
Do:
systemctl --user enable pipewire
systemctl --user start pipewire
Check again:
systemctl --user status pipewire
the result should contain:
Active: active (running)
Try again record screencast.